“VRIFICATION”: APPLYING TO DIGITAL GAMES

Daniel P. O. Wiedemann Peter Passmore Magnus Moar Department of Media Department of Computer Science Department of Media Middlesex University Middlesex University Middlesex University The Burroughs, London, NW4 4BT The Burroughs, London, NW4 4BT The Burroughs, London, NW4 4BT United Kingdom United Kingdom United Kingdom E-mail: [email protected] E-mail: [email protected] E-mail: [email protected]

KEYWORDS nificance of gaming and play in it, a need to address this Interface, Virtual Reality, VRification, Pure-VR, Former- shift from common screen-based digital gaming to VR gam- non-VR, Game Development, Game Design. ing seems apparent.

ABSTRACT Examining the topics and products presented at current gam- ing and other consumer oriented conferences (e.g. Game In the following, we discuss the process of applying virtual Developers Conference, Electronic Entertainment Expo and reality to digital games. We named this process “VRifica- QuakeCon), VR seems among the top trends. By introducing tion” and will elaborate on some of its opportunities and its head mounted display , Oculus VR revived issues. Based on a literature survey and professional practice, VR technology (Rubin 2014). Its affordability and wide de- this work covers several examples of VR games, which were veloper base has led to an expansion of VR applications. intended as such from the beginning (Job Simulator and This resulted in applying VR to digital games and other non- Lucky’s Tale) and others, which were ported to VR after entertainment forms of digital applications. A process we their initial release (DOOM VR and LizzE). We conclude have named “VRification”, to establish a corresponding vo- that, for VR games, it is essential to be optimized for the full cabulary and thus simplify the further discussion. potential of targeted interface technologies. Furthermore, porting former-non-VR games to VR can create successful VRIFICATION user experiences, when aiming for the same high standard of optimization, especially regarding simulator sickness. Applications for VRification are separated into two catego- ries: “pure-VR” and “former-non-VR”. Pure-VR INTRODUCTION applications are implemented concepts with VR as the pri- mary user interface in mind, whereas former-non-VR Very successful science fiction works like “Snow Crash” applications were first developed for common interfaces and (Stephenson 1992), “Rainbows End” (Vinge 2006) and VR was in some way applied subsequently. This work fo- “Ready Player One” (Cline 2011) over several decades illus- cuses on VRification of digital games and disregards non- trated virtual reality’s (VR) great potential in socially entertainment applications. connecting people. Otherwise physically placed all over the world, VR users could meet in a commonly shared virtual VR in its current state in games seems to be heading towards environment. One further aspect of VR, which all three nov- a broad success, as it offers various opportunities. The most els have addresses in some way, is gaming and in general obvious advantage is presence (Lang 2014). Lombard and play in VR. Relating this to our current society and the sig- Ditton describe it as the feeling of being in a realistic place

Figure 1: LizzE – And the Light of Dreams, non-VR Mode (left) and VR Mode (right) (FIERY THINGS 2013) (1997). In other words, when presence is achieved, the user VRification of Former-non-VR Games feels literally present in this virtual world and her or his body and mind will react instinctively like in the real world. This In the case of former-non-VR games VRification can pro- effect is particularly heightened by VR and seems intrinsic to vide new angles to common gameplay mechanics and its concept (Jerald 2016). It must be noted though, that real- diversify the look and feel. ism in terms of physical sensual perception, e.g. through high display resolution, low latency, binaural audio, transla- VRification needs to be handled with care though, as only tion of body part movements, haptics, olfaction etc., certain games seem suitable. When the game was not devel- magnifies the presence effect. The more senses a VR appli- oped for VR from the beginning several issues might arise, cation triggers in a realistic way, the more likely, that the like performance setbacks, which are likely to increase la- user feels present (Lang 2014). tency, which in turn destroys presence and is one of the major causes for nausea. Using less performance intensive Economically, VR seems very interesting, as developers can billboards instead of complex 3D geometry simply does not be at the forefront of penetrating a new market. Though un- work, when using stereoscopic viewing (Holding 2017). Al- clear how big this market gets, the massive growth of the so, former design and hardware interface paradigms might games market (Livingstone 2014) gives an indication. not work as well or not at all. For example, head up displays to show player attributes don’t seem to be well accepted by VRification of Pure-VR Games users (Oculus VR 2014). Other more natural, diegetic ways of offering this information might be preferable, e.g. the Other than that, by offering new interface technologies, VRi- amount of remaining ammo is displayed directly on the fication in pure-VR games raises a huge amount of game weapon (Oculus VR 2014). Furthermore, the parameters of design opportunities. camera movement (Hurd and Bettner 2014) and the reduc- tion of perceived vection seem very important (Yao 2014) From the ground up designed for VR, the Job Simulator and require more research. Graphical user interfaces like ( 2017) delivers a really successful user ex- menus need to be designed and navigated completely differ- perience for example (Stapleton 2016). The user’s purpose is ently, aiming for an optimized VR experience. Direct object to use hand controllers, e.g. HTC Vive, Oculus Touch or manipulation (e.g. via hand controllers) should be used as PlayStation Move controllers (HTC 2016, Oculus 2016 and much as possible for an increased user satisfaction (Bowman PlayStation 2016), to fulfill rather mundane and menial jobs. and Hodges 1997). Whereas the indirect Widgets and Panels These include working at an office desk, preparing dishes in Pattern should only be used for complex tasks (Jerald 2016) a diner, serving at a convenience store and repairing cars in a and should be designed for good readability and usability in garage (Stapleton 2016). Though by reducing the visuals and the context of VR. Mouse and keyboard as input devices interactive objects to a cartoonish style, lots of humorous and finally seem fairly inappropriate, given the number of but- absurd situations evolve. This in combination with some tons and being unable to actually see them. funny robotic dialogues establishes the game’s charm. The comic style has another effect, which is the reduction of re- A great VRification example of a former-non-VR game is quired performance and thus a higher possible frame rate and the DOOM VR demo showed at QuakeCon in late 2016 less possibility for simulator sickness (Pausch et al. 1992 and (ZeniMax Media 2016). In its fourth non-VR iteration, re- Jerald 2016). Furthermore because of the game’s rather sta- leased in early 2016, DOOM had a great impact on first tionary design no locomotion method is needed, as the user person shooters (FPS) by reviving some of the raw old keeps standing on the same spot. This in turn again reduces school trademarks of the genre (Shoemaker 2016). The game the possibility for simulator sickness as no vection effect is played really fast and the user is practically forced to (Riecke and Feuereissen 2012 and Yao 2014) is involved quickly move into the middle of close combat to succeed and more complicated teleportation techniques are unneces- (Shoemaker 2016). These are aspects not easily transferable sary. to VR. Moving quickly through virtual space without creat- ing simulator sickness has been a huge challenge so far. Lucky’s Tale is another successful VR experience, which There are a plethora of methods handling locomotion based was specifically developed for this medium (Playful 2016). on teleportation, physical motion, room scale tracking Being a cutely illustrated 3rd person game, like Super Mario (TechTarget 2016) and artificial input devices like common 64 and Banjo-Kazooie, it needs to overcome certain issues in controllers (Reddit 2016). The FPS genre though, lacked an VR (Hurd and Reiland 2016 and Wiedemann et al. 2016). appropriate method, which could deliver a fast pace without Though a certain amount of vection is impossible to prevent creating vection and simulator sickness. The DOOM VR in this design, the developing studio Playful made some demo seems to have solved this, by implementing a subtly clever decision to reduce the possibility for simulator sick- fine-tuned teleportation mechanic (Butterworth 2016). Using ness to a minimum. The reduced usage of user locomotion is one HTC Vive controller to fire at enemies and the other to mostly aimed away from her or his viewpoint and levels teleport-dash through space seems to even enhance the expe- were designed more linearly to avoid too much turning rience (Butterworth 2016). Though compared to other around (Hurd and Bettner 2014, Hurd and Reiland 2016 and teleportation mechanics, DOOM slows down the game to Wiedemann et al. 2016). Through these carefully crafted bullet time, when holding the teleport trigger and when re- measures and thanks to the charming character of the game, leased dashes the user in super speed to where she or he was Lucky’s Tale is a great example for a 3rd person VR game aiming (Butterworth 2016). with an old-school touch (Whitaker 2016).

Use Case: VRification of LizzE

Designing an experience that makes the most of VR, former gameplay paradigms need to be adjusted or completely re- placed. For example, in a vrified 3rd person game, the virtual camera(s) looking at a player character is not just a simple viewport into the digital world. By translating and rotating the point of view via the user’s head position and rotation, it becomes a dynamic and controllable separate entity. We noticed this effect during the VRification development of LizzE – And the Light of Dreams (LizzE, FIERY THINGS 2013), a multiplatform third-person Hack & Slay game (see Figure 2: Explanation for VR Rig Symbol Figure 1, Wiedemann 2013). (Wiedemann et al. 2016)

In the game’s non-VR version, the player looks through the screen into the game world and identifies her or himself with the player character, as she or he controls the character’s movement and actions. Playing the VR version of the game, the entity split becomes perceptible. Without looking through a viewport and seeing what surrounds the screen, but instead feeling completely encapsulated in the virtual world and in natural control of the camera(s), the player acknowl- edges her or himself as a distinct entity. Dynamically hovering over the player character, she or he feels more like a god that rather guides the player character than actually identifies with it.

This raises lots of gameplay possibilities, like looking Figure 3: Buffered pulling Camera Behavior Mode around corners, uncovering for the player character unreach- Visualization (Wiedemann et al. 2016) able spaces and objects, but also new kinds of communications and interactions between player, player As the game’s level design was not structured linearly like in character, non-player characters (NPCs) and the game world. Lucky’s Tale for example, exploration in 360 degrees was Interesting questions arise through this, like for example required and thus the user had to physically turn, when in “Why is it, that I can control character XY?”, “Am I percep- need of looking in a certain direction. Though this made the tible to NPCs?” and “Could character XY turn against me at experience more like a stand-up or swivel chair one, most some point?”. users favored this, as their natural movements added to their sense of presence (Wiedemann et al. 2016). Finally Buffered On the other hand, LizzE uncovered that a more linear level Pulling significantly reduced the vection effect and thus de- design might be supportive to a third-person VR game (Hurd creased the possibility for simulator sickness. and Bettner 2014, Playful 2016 and Wiedemann et al. 2016). Furthermore, a completely different camera behavior is CONCLUSION needed to avoid nausea through the reduction of vection. For this matter, in a previous experimental study with an adapted Concluding, a glorious and connected world of gaming in version of LizzE, we explored five different camera behavior VR, like science fiction works of Stephenson, Vinge and modes and tested them with users. An analysis of the result- Cline have propagated, is not easily established in practical ing data showed that the mode called Buffered Pulling terms. Though similarly inspired visions may already be in (Wiedemann et al. 2016) seemed to be the most promising the making and definitely on the horizon, it seems question- one for the game, compared to the other tested modes. In able that “simply” porting existing games to VR will create Buffered Pulling mode, the player character can move and good experiences. Addressing stereoscopic 3D vision (one turn completely freely in a buffer zone, without manipulating aspect of VR) in game development, the well-known game the position or rotation of the user’s viewpoint (see Figure 2 developer Fish responded similarly: Stereoscopic 3D needs and 3). Only when reaching a certain distance will the user’s to be at the back of the developer’s mind, right from the viewpoint get pulled along with the player character start, instead of trying to impose it on the game, once its (Wiedemann et al. 2016). conventional version is finished (Fish 2010). Still, in terms of former-non-VR games, technical challenges of changing existing application aspects have to be weighed against their inherent time-costs, to be adjusted or completely rebuild. We argue that games should be optimized for their technology platform and make use of the corresponding interface op- tions in creative ways to be able to become spot on, well- made user experiences.

The pure-VR examples of this paper have shown great ways Fish, P. 2010. “3-D Gaming is Waiting for Its Avatar”. URL of handling VR pitfalls, by including VR in the development http://www.wired.com/gamelife/2010/01/3-d-games/all/1 process right from the start. The decision to provide station- HTC. 2016. “VIVE™ | Discover Virtual Reality Beyond Imagina- ary jobs and a cartoonish visual style in Job Simulator tion” URL http://www.vive.com/us/ Hurd, D. and Bettner, P. 2014. “Oculus Connect: Learning from (Owlchemy Labs 2017), did not require any possibly nausea Lucky's Tale.” inducing locomotion mechanic and reduced required compu- URL https://www.youtube.com/watch?v=NbiioTWaY2E ting performance, resulting in high framerates. Lucky’s Tale Holding, J. 2017. “The Importance of Lighting in Creating Immer- (Playful 2016), on the other hand, implemented a very clever sive VR”. In VRX Europe 2017 Conference & Expo and fine-tuned combination of subtly linear level design and whitepaper, 14-20. 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